Variable speed unit and pulley therefor



Patenred Aug. 10, 1943 UNITED s'rArEs PATENT OFFICE 2326392 o VARIABLESPEED UNIT AND PULLEY :THEREFOR I o i Paul. IB. Ree'e's Columbus, In'd.,assignor to Reeves Pulley'Company, Columbus, Ind., a cor- Hporation ofIndiana Application Marek 12, 1942, serial Ni.`43'i,3 73

` v1.2 Claims. (Cl. 74 230.17)-

The present invention relates to a variable speed driving unit and apulley therefor, and is particularly directed to that type of ,unitincorporatingi one or more Variable-effective-diameter V-pulleys of theconed disctype, in which at least one of vthe variable pulleys isresiliently expansible The particular problem to which this vinventionis primarily direoted arises in connection with -installations in whicha resil- `iently expansible pulley is mounted upon, and to drive, theinput shaft of a machine, which in- `put shaft is supported solely 'bybearings in the' i machine frame, and the pulley being supported uponthe outboard projection of such shaft.V A primary object of theVirlvention is to produce la pulley, one disc of which is fixed to theshaft, the other disc of which, being axially shiftable toward and awayfrom the fixed ,disc,is interposed between the fixed disc and thesupporting bearings for the shaft, and in which the median plane betweenthe discs shall be as close as possible to the supporting bearing forthe shaft.

In the prior art, resilientlyexpansible pul- Vleys of the coned disctype have always been constructed generally in the manner illustrated,for instance, in my prior Patent No. 1,822,935, a compression typespring being interp'o'sed between the outer face of the shiftable discand a suitable abutment on the shaft beyond such outer face of theshiftable disc. Such a construction is satisfactory in installations inwhich the fixed disc may be positioned between the shiftable discand thebearing supporting the shaft upon the outboard projection of which thepulley is mounted. But in certain installations,

it is not feasible so to arr'ange the fixed disc between the shiftabledisc andsuch bearing.

To the accomplishment of the above and related objects, my invention maybe embodied in the form illustrated in the accompanying drawing,attention being called to the fact, however,

that the drawingis illustrative only, and thatV present inven- 54 inresponse toa vided .with an elongated hub lprojecting from itsjconedface, and a mating disc lvissplined on said hub IS through themedium ofa key |1,`o r the, like, `A hubfli projects rearwardly I from that face`of said disc IB oppositeitsconed face, and fiiredly carries theinnerrace l9`of a thrusti bearing, the outer race 'Eli of which fixedlysupports a bearing housing Zi.` Said bear'- ing housing 2| vis providedwith a, pair lof diametrically oppositely projecting pinsv 22 upon whichis supported an equalizer ring 23.! A pair of screws 24,'feach QOdegreesremoved 'from the i pins 22, secure tothe equalizerring yoke arms 25carried by'a'nut 2% threadediy niounte'd uponV a screwshaft 21 which isrotatablm butV I non-reciprocably, supported in a bearing'28 carried bythe base Ill, a hand wheel 29 being suitably operatively associated with'the screw-, i

shaft 21. o, v

Itwill be obvious that, as `the hand wheel 29 is rotated in onedire'ction or the other, the nut 26 will beaxiallyshifted in onedirection or the other (non-illustrated means being provided'forrestraining the nut 26 against rotation) to shift the. disc VIGpositively toward oraway from theV disc |3.

VAn edge-active belt 54 is engaged between the lconed faces of the discs|3 and |5, and'will'oc'- cupy Variable radial positions between thediscs |3 and IS, depending upon the relative positions of said* discs,to Vary the lineal speed of the belt given angular Velocity of thepulley [4; f

i Now,V it will b'e obyious that, for Optimum 'convenience' ofloperation 'of the pulley vll, the

shifting mechanism must be positioned adjacent that side lof 'the pulleyremote from the motor andl that, again for Optimum convenien'ce andsimplicity of construction, this means that 'the shifting mechanism mustact upon that disc of the pulley |4 which is remote from vthe motor :Il. ltis a Vfeature v of constructions of the typehere'under'consideration that; as the shiftable 'disc is axially moved,the position of vthe me- .'dian plane of the belt will' Shift axially..That if the disc |6 is moved away from the'disc E3, the-belt 54 willmove inwardly across the faces lof the discs |3 and IB; and, sincethedisc I3 .is

fixed, that movement of the'belt will necessarily cause axial travel ofthe belt downwardly,'as Vviewed in Fig, 1. i i

This means that, in installations of the kind here under consideration,it is essential that the Vfixed Vdisc of the driven pulley must beaxially Ofiset and `oppositely faocing with respect to the 32, in themachine frame.

the machine 33 must be supported .upon the outboard projection of theshaft 31: and it is` nb-x,

' external thread 38.

viously desirable to avoid the necessity for providingr an additionalbearing at the `outer end of the outboard projection of said slfiaftfThe pulley, indicated generally by the reference numeral 33, is thedriven pulleyreferred ic-above.

Itsl fixed discrnust face oppositely with respect to the fixed disc V|3of the driving pulley `|-4-. It

,follows'that the shiftable disc must be .interpo$d between the fixeddisc .and the bearing'32.. 'If a construction .like that villusti'ateiiin my priorPatent No. .1,822,935 were used, the spring .9 Vof thatpatent would have to .be intrposed .between 'the pulley on the shaftprojection 31 andlthe bearing 32. which :would mean V.that .the'median,piano of the driven ;pulley wouldhave .'to'be positioned far out beyondthe `bearing 3.2. so that the radial The input pulley fo'rf intoengagement with the shaft 3| to fix the elethe mating disc 35.

ment 4| and the barrel 44 to said shaft.

Thus the pulley 33 comprises a disc 35 fixed to the shaft 3|, a disc 34axially shiftable with respect' to said disc 35, anda tension spring 40,positioned wholly on that side of the disc 34 remote from .the bearing.32.,zbut constantly urging the disc 34 away from the bearing 32 andtoward And as a result of this construction, it lispossible to positionthe shiftable disc 34 clcseiyadjacent to the bearing 32, therebyiocating the median .planepbetween the discs (inV .'Whioh -planesubstantially the entire radial stress stresses resulting .fromthedriving torue would be applied to' .the shait proicction 31. atapoint ,fa/r removed from the bear'ing 3.2,.,and there would .be acertain. amount of whipor vihration in the shaft projection which wouldhavee deleterious 'effect not lonly upon the shaft-itse1fbut-alsouponthe belt and the component parts oftl'xe transmission. V v

. To .overcome vthese difficultiesi have .provided the peculiarconstruction illustrated in thepresent application. vThe pu11e1y33.comprises za shiftable .disc 3,4v end a .fixeddisc 35, 'Ihe shiftable.disc .34 is spiinedto .the sbaft projection 3+ through-the medium .of`a key .35. or the like, .and

.is provided withV hub 3.7! proioctinx axialtv from Vits coned...fa,ce.said hub being fonned with an uponthe thread 38 ofthe hub 31.- i

hub element 41 isformedwith an external Two or three turns 30 at one i I.end of acciledspring 40 :are threadedly engaged .thread 42; -a'cd twoor .three tums 43 at the opim- Vsite end o fthe spring 40 are thresdedlyengaeed upon the thread '42 .of the hub element ll. :'Ifhe spring 4B isso proportioned that, in its rclaxed condition. the distan .between themms-3B and resul-tmgffmm 'the driving efiort is exerted against.thezshaft :3.1) Very -close to the bearing 32.

Itwill be clear from an inspection of Fig. 1 that, as the disc 'IG ismoved away from the (lis: 13.. :the resilient .action of the spring 40will cause the disc 34 to move toward the disc thus sdueezing the 'belt;55 outwardly between said '*disosandnpuliing the belt inwardly betweenthe dises |3and i''. Such radial movement of the be'itbetween'the discs13 and Hi 'wiiLas above describedycausenthe Umed'lanv'plane of 'thebel-tI to hifti downwardly asyiewed in Pig. 1, as the 'belt traifelsover theconed face of the disc '13; but'it 'will .be perceivedthat thatmovernent of the beit isV acconipanied 'by a corresponding movernent ofthe opposite end of the beit acrossthe coned face of -the 'fixed disc1.5, so that the two .ends of the belt move downwardly to the 'sameextent, Whereby the .median plane of the 4belt .is held parallel toits'illustrated position. Now,v if. the Adisc34 were the fixeddisc, ,it'wi-ll be obyious that, assthe left- Vhand end -of the beit movesdownwardly through traveiing 'inwardly Vacross the facefof thedisc 13.the right-hand .end of the belt would move upward'ly .as a resultoffltraveling outwardly across the .face of'the disc 34; and' suchmovement Would result in twisting of the helt which would greatlyincrease the wear uponthe belt. It 151 for this reason that .it isssential that 'the `s'lfiiftabie discs of the two puileys shall be:oppositely Iaced; and it'is for thisr'eason that it is essent'ial to.go to some such construction paspthat which I have yillustrated in .thepresent disclosurein order .to attain the advantage of positionng themedium Diane of the bcltlas close the turns 43 is less than Vthe minimumdista'ne. z

between the thread 38 and thethread 42.. .'Ilhus,

even when the coned faces of. the discs 34 and 3.5

arepincontact with eachpther, thesprr-ing 40 will as possible to thebearing .32, while .retaining the simplicity of construction of theshiiting Ineohanism Vfor the disc JB.

`lIn nie. z I have jiuustrated a different shirt- 'ing `inechanism. Upon.the base 111' .is mounted under tensicn, and tonding .to A''flzil'itreict still The hub element 4 l :is vsleeved upon-.the shaft.3]

within a barrel Mformed upon, .and projectinsz maxiei'lv rearwo rdlfvfrom. that Vface of thedise .35 remote from thedisc Mthe intcrior 4:5 ofsaid barrel opening coa'xialiy thrmigh 'the 'conedfaoe of the disc 35.The internal .dianieter .of the :barrel is suffioiently larger thantheldiameter of .the hub 4| and the 'hub C'l'flV to house the spring 43.

the same motor vH .carrying, on .its spindle, the nulleyV 14 comprisingthe'discs .13 and '1.6. The

hub |.8 of the disc IS .carries the pbearing race iii, while thebear'ingrace 20is fixed .in the bearing housing 2|.-on the pns-22 ofwhich is mounted the equalizer'ring. 23. Screws .24 se.-

- cure to the equalizerV ring the .arms 25' carried by the nut25'whichis'threadedly mounif VVed on a .screwshaft 5.0 vrotatably butnon-reits extren'iity,` the rfa'rre-l 44 'is f-orriedwith an opening-45snugly sleeved Vupon the outei'end'of the hub element 4|. A threadedbore. 41 'in the outer end of the barrel 44 may he registered with athreaded bore 48 in the hubelement H, for the conioint receptionrof aset screw`43V which-provides a'rigid connection between the barrei 44and the element 4|, and which can be turned down ciprocablysupported .inhearings 51,752, and-53 on the base IO'. 'hand wheel 29' may. in thisembodiment of the invention, be .mounted upon either end of. thescrewshaft 5.0.

It will be obvious that' the vpulley 33 finds utility not only in theparticular type of'idrive illustrated herein, but also in that type ofdrive in which oneV of the pulleys is of invariable dlameter, and thespeed Variation is attained' by varying the center distance between the'beltconnected pulleys.

*i I claiin as my inventonf:"'i

1. In a variable-speed unit'fafpair'of substantiall parallel shafts, afirst'coned disc fixed to one of said shafts, a secondconeddisc'axialvly s'niftably mating with said fixe'd disc, means`foraxially shifting said second'disc, a third coned disc fixed to theother of said-shafts and oppositely facing andl axially offset With'respect to said firstidisc, a fourthiconed disc axially sion springmeans urgingsaid Vfourth disc` toshiftably associated with said thirddisc, ,ten-

mating relation to said first disc and separated rom said bearingv bysaid first disc, a single coiled spring sleeved on said shaft andseparated from said bearing by said first disc, said spring beingconstantly expanded beyond its condition of equilibrium, whereby saidspring continuously tends to contract to urge said first disc towardsaid second disc, an edge active belt operatively engaged between saiddiscs, power delivery means operatively engaging said belt to drive thesame, and means for variably determining the radia] position of saidbelt between said discs.

3. A speed varying pulley comprising a first coned disc and a secondconed disc adapted to be mounted in facing coaxial relation With saidfirst disc, said second disc being provided With a coaxial extensionprojecting rearwardly from, and opening through, its coned face, and' acoiled spring nested in said extension and having one end securedtherein, and means securing the oppositeend of said spring to said firstdisc, the relaxed length of said spring being' 4. A speed varying pulleycomprising a first said barrel, the opposite end of said spring be-Vconed disc having a hub coaxiallyzprojecting i from its coned face, athread formed on said hub, a second coned disc adapted to be mounted inmating coaxial relation with said first disc, said second disc beingprovided with a coaxial extension projecting rearwardly from, andopening through, its coned face, a coaxial hub mounted adjacent theouter end of said extension and formed with a thread, and a coiledspring having at least one of its turns at one end threadedly secured onthe thread of one of said hubs and at least one of its turns at itsother end threadedly secured on the threads of the other of said hubs,the relaxed length of .said spring being less than the minimum distancebetween said threads.

5. The combination with a shaft of a coned disc axially shiftablymountecl on said shaft and i adjacent one-end thereof beingthread'edly'seicured on the thread of said hub and* at 'least f turnswhen said spring is relaxed being less than the minimum' distancebetween the thread of said hub and said threadedmeans. i v

G'The combination with a shaft of' afconed disc' axially shiftablymounted on said shaft,C a second coned, ,disc"arranged on said-shaftjincoaxial'mating relation with said'firstdisc, a 'coiled spring sleeved onsaidl shaft, an'ielement fixedto said shaft `and positioned on-thatsideof said second discremote fromv said Shiftable disc, saidspring havingone end fixed to said element and the other end fixed to said shiftabledisc and iurging'thelatter toward said second disc, and means holdingsaid second disc against axial movement with respect'to saidshaft. V

7. The combination with a shaft of a coned Vdisc axially shiftablymounted on saidshaftyasecond coned disc'arranged on said shaft 'incoaxial mating relation with said first disc, 'a

coiled-spring sleeved on said shaft, an element fixed to said shaft andpositioned onthat side of said secondV disc remote from said shiftabledisc, said spring having one endV fixed to said element and the otherend fixed to said shiftable disc and urging the latter toward said sec-vond disc,` and means removably securing said second discto said element.

8. The combination with a shaft of a' coned I disc axiallyshiftablvmounted on Vsaid shaft, a second coned disc mounted on saidshaft 7 in coaxial mating relation-with said first disc, said seconddisc being provided with a Vcoaxial barrel projecting rearwardly fromthat faceV of said ing secured to said element, and means removablysecuring said barrel and said element' against movement axially of saidshaft.

V9. The combination with a shaft of a coned disc axiallyshiftably'mounted on said` shaft, a second coned disc mounted on saidshaft in coaxial mating relation with saidjfirst disc, said second discbeing provided with a coaxial barrel projecting rearwardly from thatface of said second disc remote from'said first disc, a coiled springsleeved on said shaft and having one end secured to said first disc, theopposite end portion of said spring being received within said barrel,an element fixed onsaid shaft within said barrel, the opposite end ofsaid spring b-eingvsecured to said element, and means removably'securing said barrel against movement relative to said element.

10. The combination with a shaftof a coned disc axially shiftablymounted on said shaft, a second coned disc mounted on said shaft incoaxial mating relation with said first disc, said second disc beingprovided with a coaxial barrel projecting rearwardiy from that face ofsaid second disc remote from said first disc, opening through the conedface of said second disc, and provided with a coaxial opening in itsrearmost end, a coiled spring sleeved on said shaft and having one endsecured to said firstdisc, the opposite end portion of said spring beingreceived'within said barrel, an element sleeved on 'i' 'i said vshaft'Within said barr81,'.the0pp0site end of saidspring 'being secured vtosaid element,

said opening at the rearmost end ofrsaid' barrel being sieeved over saideiement, and means remo'vabiy'securing .Said ybari'ei-and said elementagainst moi/ement 'relative to ;each Vomal-,21m1 :to

' saidshaft. w

11. In' a variabl-e speed unit,V a pair of substantial'ly parallelshafts, a fi'rst caned disc fixed to oneof said ,shaf-tsQa secondcon'edfdisc ax-ialy shifta-bly mati-ng with said fixed disc, means toraxialiy shifting saidseoond'disc, a 'third zconed disc fixed to theother 'of said shazfts andV oppositeiy'facing and axidly` offset with'respect to said lfii'st disc, a fourth coned disc axialiy shiftablyassociated with said third disc, 'a single coi'ied spring sleeved onsaid other shatrand constantly expanded beyond its condition ofequiiibrium, said spring being operat'iveiyassociated with said thirdand fourth discs,`to urge said fourth disc constantly toward said thirddisc, and an edge active belt providing Va driving connection betweensaidiirst and second ,discs and V said third and fonrth discs.

V12,. In a variablespeed unit, a pair :ofsubstantially parallel shafts,a variable diameter :pu11ey ,driving1y supported `from onercofv said-shafts andcomprising -a pair of relatively axial- 'iy ,shiftable facingconed discs cooperating to iorm .a pulley. of variable effectivediameter, means forV effecting r'elative axial movement lof said discs,a second' variable diameter pulley drivingly supportedfrom one ofsaidshaftsand comprising .a second pair4 of relatively axially shiftablefacing coned discs cooperating to Vform Va pulley of Var-iable effectivediameter, a single coiled spring sleeved' on said other shaft, posi-.tioned .between said last-mentioned discs, and

CERTIFICATE OF CORRECTION.

Patent No. 2,526,592. August 10, 19LL5.

PAUL B. BEEVES.

of the above numbez'ed patent requifng correctiorf asfollows: Page 5,first column, line 18, clam 2, for "outward" r'ead --outboard--,- and.that the said Letters Patent should be read with this corr'eetionthelrein that the same may confor'm to the record of the case in thePatent Off Sgned and sealed thisI lLth day of September,l A. D. 19L5.

Henry Van Ar'sdale,

(Seal) Acting; Commissioner'of Patents.

